1. Field of the Invention
This invention relates generally to flooring units useful for distributing the wiring of various electrical services, such as, power, telephone and communication wiring throughout the floor of single story and multi-story buildings; and more particularly, to a field-assembled cellular decking unit providing plural, generally parallel, enclosed cells.
2. Description of the Prior Art
Cellular decking units are known which provide in-floor raceways for distributing electrical services, such as, power, telephone and CRT services. Such a unit is disclosed in U.S. Pat. No. 3,459,875 (FORK) wherein three enclosed cells separated by lengthwise troughs are provided. Conduit means connecting a first set of adjacent cells and outlet openings formed in a second set of adjacent cells provide access to all three electrical services at a single location in the flooring unit.
Another type of decking unit is known wherein an elongated upper metal sheet, having an inverted hat-shaped profile, is secured to a generally flat, corelative lower metal sheet along contiguous portions thereof. The lower metal sheet presents at least one partition, formed by a re-entrant bend in the lower metal sheet, which projects upwardly therefrom into engagement with the upper metal sheet and which extends along the entire length of the lower metal sheet. That is, a relatively wide single cell decking unit is divided into separate, adjacent subcells by one or more partitions integrally formed in the lower metal sheet. Such a decking unit, commonly known as a plural-cell duct, finds utility in reinforced concrete floor structures wherein the unit is not intended to serve as a structural component of the floor structure. Examples of such plural-cell ducts are disclosed in U.S. Pat. Nos. 3,751,576 (KLINKMAN et al) and 4,338,484 (LITTRELL).
Heretofore, cellular decking units have been factory-assembled for ready installation in the field. Known cellular decking units, as manufactured in their finished form, consist of at least two formed metal sheets welded together. Factory-assembled cellular decking units require extensive handling and production in the factory. Additionally, since factory-assembled cellular decking units do not nest readily with one another, higher shipping and handling costs are incurred in transporting the units from the factory to the field. Another disadvantage of presently known configuration of factory-assembled cellular decking units is that the amount of metal used to construct the unit exceeds that amount needed to support floor live loads.
Panel units are known which are adapted for field-assembly to form roofs, walls and floors. Such panel units may have a generally z-shaped or S-shaped configuration wherein a first half of a first panel unit overlies the second half of an adjacent second panel unit, and a second half of the first panel unit underlies the first half of an adjacent third panel unit. See for example U.S. Pat. Nos. 2,026,278 (HIGLEY) and 2,899,028 (WALKER). Another such panel unit presents a corrugated lower section having a flat wing-like upper section extending laterally therefrom. When assembled, the upper section of each unit caps the corrugated lower section of the adjacent unit to provide a cellular construction. See for example U.S. Pat. No. 2,873,008 (ASHMAN).
The HIGLEY and ASHMAN constructions present a relatively flat upper surface which cannot coact compositely with an overlying layer of concrete and do not appear to be readily adaptable for the distribution of electrical wiring. One WALKER construction produces a subfloor/concrete structure which can be used to distribute electrical wiring. However, the use of preset access housings for accessing the wiring, requires a thicker-than-normal concrete cover.